Celebs with similar background:

Her father was Mikhail Vodianov. Her mother was Natalia Victorovna Gromova. Her maternal grandparents were Victor Filippovich Gromov and Larisa Gavrilovna Gromova.
Natalia stated that her paternal grandmother was of Mordvin ancestry. (Russian http://www.youtube.com/watch?v=8reAdQbNEms). Mordvins divided into Moksha and Erzya. I don’t know what exactly was her grandmother.